A resin composition is used as a sealing material or an adhesive for a wiring board, a circuit board, a circuit plate including multiple layers of wiring boards and circuit boards, a semiconductor chip, a coil, an electrical circuit, an automobile component, and the like. Such a resin composition is required to have heat resistance and properties of rapidly curing (hereinafter, sometimes referred to as “rapid curing properties”).
For example, Patent Literature 1 discloses an epoxy resin composition obtained with an addition reactant between unsubstituted imidazole as a curing agent and bisphenol-type diglycidyl ether. Such an epoxy resin composition rapidly cures, and can form a cured resin layer which is voidless and has excellent adhesiveness.
Patent Literature 2 discloses a thermosetting resin composition which includes a copolymer resin containing a curing agent having an acidic substituent and an unsaturated maleimide group, dicyandiamide, and a specific monomer unit, and epoxy resin. Such a thermosetting resin composition has metal foil adhesiveness, heat resistance, and the like.